Cutting chain



A118 5, 1952 A. B. REID CUTTING CHAIN Filed oct. 2o, 1949 7772520715 Reid A wastage of wood.

Patented Aug. 5, 1952 CUTTIN G CHAIN Anthony Brendan Reid, Lansdowne, Ontario,

` Canada `ApplicationOctober'20,l 1949, Serial No. 122,397

5v claims. (o1. 14s-135) This invention relates to chain saws, and more particularly to the cutting chain structure thereof. One of the chief disadvantages of presently available chainv saws "is the relatively Wide ker produced in the sawing operation, such widefkeri being an inherent result of the cuttingA chain structure. While it is obviously desirable-to provide a` saw which will take out -a minimum of wood in the sawing operation insorder tospeed up the sawing operation, conserve woodv and employ as little driving power as possible, the minimum widthL of kerf producedA by present day cutting chains is substantially three-eighthsjof an inch. Moreover, such saws usually consist'of a relatively large number of different parts and manufacturing ,and maintenance costs are high.

Itis an object of this invention to provide a cutting chain o f simple and inexpensive structure and having a rrelatively narrow overall thickness wherebythe `sawing operation is conducted` with greater-speed, less power consumption, and less yTo this end, the invention contemplates the provision of a cutting chain comprising a plurality of pivo'tallyconnected links, each link having a body portion and leading and trailing Aportions lying in a common plane laterally offset from the plane of the body portion,.and a tooth carried by at least the trailing portion of each link.

The invention will be described with reference to the accompanyingdrawing, in which,

Figure 1 is a side elevation ofja portion of a cutting chain in accordance with thev invention,

Figure 2 is a plan rview ofthe chainshown in Figure 1, v

Figure 3 is an end elevation of the-chain shown in Figure 1, -v

Figure 4 is a plan view of a slightly modied forml of cutting chain, Y

Figure 5 is a side elevation of a of links, and

Figure 6 is a sectional end*v elevation of a rivet connection for the links. Y f

v.Referring to Figures l, 2 and 3, the cutting chain shown comprises four diierent links, I, 2, 3, 4, arranged in a plurality of successive series of six links each, the consecutive order of links in each seriesbeing 1, 2, l, 2, 3, 4. f

All links'are formed from metal plate of `uniform thickness throughout and each possesses structural characteristics common to those in the other links of the series, and including body portions 'I lying in a common vertical plane. Alternate links I and 3 havea trailing portion 8 and a leading 'portion 9 both also lying in acommon vertical plane but laterally offset in one direction from the rst plane. The other alternate links 2 and II have a trailing portion I and a leading portion II both also lying in a common vertical plane but laterally offset in the opposite direction from the rst plane. The degree of oliset in each case is preferably one-half the thickness of the modified form metal plate whereby the overall width of the chain is not greater than twice the thickness or the metal plate from which the links are formed. A part I2 of each body portion I extends downwardly, as shown, to provide a plurality of spaced guide and sprocket engaging members. AsV shown in Figure 1 and 3, the parts I2 travel in the usual grooved chain guide I3.

The links are assembled to form a chain with the leading portion of leach link overlapping theV trailing portionof the next succeeding link, such overlapped portionsl being pivotally connected as byrivets I4. As shown, eachlink has a counter-` bored'cpening I5 to receive the head of the'rivet and a flared opening IG to enable the driven .head

of the rivet to be countersunk. AIt will be observed that the rivets are applied alternatelyfrom each side of the chain. In order to positively prevent.

the rivet from turning in the structure, it is p'roposed to provide a notch I1 in the vsv/'all opening I6 to receive a portion of the rivet whenvthelatter is driven. Such a rivet structure prevents'loose'n-` ing of the rivet and resultant failure of the chain.

Since the overlapped portions are reversely'o set half their thickness, the exposed sidesuifaces of the overlapped portions each lie in avetical plane spaced outwardly from lthe adjacent surface of the body portion 'I a distance equal to half the thickness of such body portion, as clearly shown in Figure 3.

The trailing portion of each link carries an upwardly extending tooth structure, Athe leading portion of each link being free from a tooth structure in the Vmodiiication shown. Link I,. oiset portions of which are directed towards the right,

has a cutter tooth I3 carried by its trailing portion 8. Link 2, the offset portions of which are directed towards the left, has a cutter tooth I9` carried by its trailing portion I0; Link 3, the oiset portions of which are directed towards the.

right, has a raker tooth- 20 carried by its trailing portion 8. Link 4, the offset portions of which' are directed towards the left, has a raker Ytooth 2l carried by its trailing portion I0. v

Cutters I8 have a right hand set andcutters I9k a left hand set, as shown, the angle of set varying in the usual manner with the typeofwood and operating conditions. The angle ofY set has' been somewhat exaggerated in the drawing for clarity of illustration. Raker teeth 20- and 2| maybe.: inclined inwardly towards the planejof body por-.

tions 1 for more effective operation. s

The arrangement of links may be varied widely within the scope of the invention. Figurexl, illus trates one modified arrangement,` whereinthe same links are employed but in different order.

Asshown, the consecutive order of links in each,

fseries of such modified arrangementis 1, 2, 3, 2,

l, 4. It will be observed that but two basic linkA structures are employe-d, namely, that from which links and 3 are formed and in which the`olset Thus,-

4 a tooth .integrally carried by said trailing portion of each link. l

2. A cutting chain for saws having a plurality of successive series of pivotally connected links,

operations, and the desired tooth structure subsequently formed thereon.

Figure 5 illustrates a somewhat modified form of link structure. Two connected links 22 and 23 Y are shown, similar to the links previously described and having similar body portions 1, respective trailing portions and Ill, and respective leading portions 9 and Il. The trailing portion of each link 22, 23 carries a respective tooth 24, 25. The trailing portion of each link also carriesy a rearwardly extending vprojection 25,' which in normal or longitudinally aligned position of the links remains in overlappedrelation with the leading portion of the adjacent link, but which, when onelink swings out of alignment with the adjacent link (as whentravelling around the usual chain-supporting sprockets), moves upwardly into the space between teeth 2A and 425a,

as shown in dotted lines in Figure 5. Such projection 26 Vacts as a means for loosening and cleaning out accumulations of sawdust between theteeth of the saw. l

It will b e observed that the bodyportion l of each linkis conveniently of .triangular shape, i. e., the offset portions of the link are pressed outwardly from the plane ofthe bodyportion along upwardly converging lines 2l and 23. It is proposed that the rear edge 2S of links .22., 23 which constitutesthe rear edge of projection 2t, be inclined to coincide substantially with line 28 of the body portion ofthe adjacent link. Thus, in the form shown in Figure 5, engagement of the upper portion of the edge 29, as extended by the projection 26, with the relatively projecting edge of such body portion, as defined by the line 28, will tend to prevent upward swinging movement of one link relative to the other and consequently facilitate handling and operation of the chain.`

vThe chain described may be manufactured in a convenient and inexpensivejrnanner. The links are associated with veachother in such manner that the overall width of the chain is restricted to a minimum andthe kerf cui; by such a chain is substantially narrower than that resulting from use of heretofore proposed chains. Thus, a". chain constructed in accordance with the invention will cut a kerf at least .as narrow as threesixteenths of an inch in width,H with resulting considerable saving in wood and power. l

What is claimed is:

1`. A cutting chain for saws having a plurality of'successive series of pivotally connected links, said links each being of unitary structure and having a body portion, a trailing portion and a leading portion, said body portions being arranged to lie in a common plane, the trailing and leading portions of each alternate link being arrangedV to lie in a common plane laterally offset in one direction from said rst plane, the trailing andleading portions of each of the other alternate links being arranged to lie in a common plane laterally olset in the opposite direction from said first plane, the leading portion of each link lying in overlapping and laterally abutting relation with the trailing portion of the next succeeding link, said overlapped portions having a pivotal connection extending therethrough, and

said linkseach being unitarily formed of metal of uniform thickness and having a body portion, a trailing portion, and a leading portion, said trailing and leading portions of each alternate link lying in a common plane and being laterally offset in one direction from the body portion, and the trailing and leading portions of each of the other links lying in a common plane and being laterally offset in the opposite direction from the body portion, the leading portion vof each link lying in overlapping and laterally abutting relation with the trailing ,portionV of the next succeedingflink, said overlappedgportions having a pivotal-I connection extending therethrough, and a tooth l integrally carried bythe trailing portion of'eachlinky l y y 3. A cuttingfchain for saws as defined in claim 2, wherein certain of'said teeth constitute cuttingr teeth and certain others of said teeth constitute raker teeth. Y V y v4l. A cutting chain forsaws comprising a plurality of seriesv of links, each said linkV being unitarily formed from metal plate and having a body v portion, a trailing portion and a leading portion,

the trailing and leading portions being laterally offset from the plane of the body portion, a tooth integrally Vcarried by one of said offset portions, the leading portionv of each` link lying overlapping abutting relation with thetrailing` portion of the next succeeding link, means pivotally connecting together said overlapping portions, j the trailingportion of each: link having a'rearWa-rdly extending `projectiom's'aid projection having anv upper edge normally' lying in substantially the saine plane asY that of the upper' edge of the body portion of the adjacent link but moving upwardly in rel-ation to said upper edge ofthe body portion in response to rotative movement of one link with respect to the nextsucceeding link, the juncture between said trailing v,andleading portions and said body portion `being along a pair ofupwardly converging lines, said body portion having a substantially triangular coniguration, and the rearward edge of said projection being inclined and-substantially coinciding with oneof said lines of the next succeeding link.

5. In a cutting chain for saws having a plurality of successive series of links, said links each having a flat body portion, the body portions of the links lying in a common plane, and flat leading and trailing portions lying in a common plane laterally offset from and parallel to the plane of the body portion, the leading portion of each link lying in overlapping laterally Iabutting relationV with the trailing portion of the next succeeding link, said overlapped portions havingV a pivotal connection extending therethrough, at least one link of each series having-a tooth'carried by said trailing portion. f

ANTHONY BRENDAN REID.

REFERENCES, CITED The following references` are voi? lrecord in the file of this patent:

UNITED STATES PATENTS Number name Date 1,363,171 Sly Dec. 21, 1920' 1,634,644 Bens July 5, 1927 2,351,112 Day June 13, 1944 2,508,784 Cox May 23, 1950 

